What the best gasoline mix to use?

[Ron61]

If you have aluminum heads you can get by on less octane. With my iron heads I can get by cruising around with about 5 gallons of 110 leaded racing gas to 15 gallons of pump gas. But the hotter it gets here, the more racing gas I have to add to avoid pinging. Also my CR is just 10.5/1.

Ron

[patrickt]

Originally Posted by Ron61

If you have aluminum heads you can get by on less octane.

Yep, and if you have a cam that politely keeps the intake valve open longer you can get by with even less octane. Your ear should tell you though whether you can live with pump gas or not. Having to ferret out race gas is a pain in the butt.

[bret a ewing]

Originally Posted by Ron61

If you have aluminum heads you can get by on less octane. With my iron heads I can get by cruising around with about 5 gallons of 110 leaded racing gas to 15 gallons of pump gas. But the hotter it gets here, the more racing gas I have to add to avoid pinging. Also my CR is just 10.5/1.

Ron

Ron,
Pump gas meaning Sunoco Ultra? (93 oct)

[patrickt]

Originally Posted by bret a ewing

Ron,
Pump gas meaning Sunoco Ultra? (93 oct)

You could always hunt for one of those old Sunoco "dial-a-pumps." Remember? You turned the knob on the side of the pump and you could turn it up all the way to Sunoco 260.

[FWB]

with a 11:1 and alum. heads i find pump gas works with no ping (maybe)
however i do notice a 10-15 deg hotter temp with pump gas alone.
the "real lead" that was mentioned does exist and works well. i use 1\2 quart
of the stuff linked at bottom in a full tank and i can idle at traffic lights all i want
even the sound of the motor is better, it really likes it. this product is
tetraethyl lead. i cannot tell the difference in driving or plugs comparing racing
fuel(leaded 110) or 93 octane exxon\mobile with kemco's lead added


www.kemcooil.com/products.php?cId=4